Both captains in the 1965 England-South Africa Test series wore glasses - was this unique?asked Richard Whitehead from London
Both captains in that 1965 series - MJK Smith for England and South Africa's Peter van der Merwe, who died recently - did indeed wear glasses. As far as I can tell, that was the only occasion that bespectacled captains have opposed each other in Tests: the only other regular wearers of glasses to skipper Test teams appear to be Clive Lloyd, Zaheer Abbas, the New Zealanders Daniel Vettori and Walter Hadlee, and the Indian pair of the Maharajkumar of Vizianagram and Pankaj Roy - and none of them captained against each other. A few others started in spectacles but switched to contact lenses (Geoff Boycott and Anil Kumble were lens-wearers by the time they captained), while others needed glasses later on: Geoff Howarth was one such, but I don't think he wore them when he captained against Lloyd's West Indians in 1979-80 (Lloyd might have switched to contacts himself by then anyway). There may be some early players we don't know about: England's first captain against South Africa in 1888-89, C Aubrey Smith, certainly needed spectacles later in life - as an old man, playing for the Hollywood club in California, Smith asked his butler to fetch his specs after he dropped a catch at slip. Next ball he dropped another one, and blustered: "Damn fool brought my reading glasses."

I noticed that five batsmen scored centuries for Pakistan against Bangladesh at Multan in August 2001. Was that a record?asked Rahul Memon from Delhi
Five of the six who batted in Pakistan's innings of 546 for 3 in Multan in 2001 reached centuries (Inzamam-ul-Haq retired hurt immediately after reaching his): I've always felt a bit sorry for the man who missed out, Faisal Iqbal, who was bowled for 9. Five centuries in the innings equalled the Test record, set by Australia (758 for 8 dec) against West Indies in Kingston in 1955. There has been one other instance of five in first-class cricket, by New South Wales (918) against South Australia in Sydney in 1900-01, but the overall first-class record is six individual hundreds in the same innings - by Holkar (912 for 8 dec) in their Ranji Trophy semi-final against Mysore in Indore in 1945-46, when the centurions included the 50-year-old CK Nayudu.

Greg Chappell was awarded the nickname "Chappello" after a run of ducks in 1981-82. He was out for 0 four times in that season's one-day World Series Cup - is that the record for one competition?asked Greg Lorimer from Australia
Greg Chappell was the first man to collect four ducks in the same one-day competition, although it should perhaps be pointed out that the Australian tri-series back then was a long drawn-out affair - Chappell played 14 matches in it that season. Since then, three other unfortunate batsmen have bagged four ducks in the same one-day competition: England's Ian Blackwell in the one-day series in Australia in 2002-03 (ten matches), and South Africa's AB de Villiers (ten) and Kyle McCallan of Ireland (nine) in the 2007 World Cup. The achievement of de Villiers was notable since, at that stage of his career, he had never been out for a duck in a Test match.

When Somerset played Yorkshire at Taunton in May 2011, Marcus Trescothick and Arul Suppiah shared double-century opening stands in both innings. How often has this happened in first-class cricket?asked Eric Cole from England
Trescothick and Suppiah had opening stands of 257 and 228 (unbroken) in that match against Yorkshire in Taunton in 2011. It was the fourth instance of the same opening pair sharing two double-century stands in the same match, following Bert Sutcliffe and Don Taylor (220 and 286 for Auckland against Canterbury in Auckland in 1948-49), Paul Pollard and Tim Robinson (222 and 282 for Nottinghamshire v Kent at Trent Bridge in 1989), and Graham Gooch and John Stephenson (227 and 220 for Essex in Northampton in 1990). There is also one instance for the second wicket: for Sussex against Nottinghamshire in Hove in 2000, Richard Montgomerie and Michael Bevan put on 292 in the first innings and 265 in the second.

Which bowler has taken the most wickets in a calendar year in Tests, and ODIs?asked Anil Malhotra from Mumbai
The leader in Tests is Shane Warne, who took 96 wickets in 2005, 40 of them in the Ashes series in England. Muttiah Muralitharan came close to that the following year, with 90, and he's also joint-fourth on the list with 80 in 2001 (Allan Donald also took 80, in 1998). In third place is Dennis Lillee, with 85 Test wickets during 1981. Leading the way in one-day internationals is the Pakistan offspinner Saqlain Mushtaq, who took 65 wickets in 1996 and broke his own record with 69 the following year. Warne (62 in 1999) comes next, just ahead of three bowlers with 61 - Anil Kumble (1996), Abdul Razzaq and Shaun Pollock (both 2000).

Jack Hobbs scored the most centuries in first-class cricket. Did he also score the most in the County Championship?asked David Williams from Edinburgh
Jack Hobbs scored 199 first-class centuries (or 197 by some calculations), nearly 30 more than the next man, Patsy Hendren (170). But a lot of Hobbs' hundreds came for England, in Tests or on several tours, or for the Players: only 130 of them were in the County Championship, and he is beaten on that count by the prolific Hampshire batsman Phil Mead, who made 132. Only four other batsmen have completed a century of Championship centuries: Hendren (113), Frank Woolley (112), Wally Hammond (106) and Mark Ramprakash (103). Mead also leads the way for runs scored in the Championship, with 46,268: Woolley is next with 43,703, ahead of Hobbs (38,737), Hendren (37,418) and Herbert Sutcliffe (32.814).

And there's an update to last week's question about the highest and lowest international grounds,from James Dignan and others via Facebook
"Bourda in Guyana is almost certainly the lowest ground that has been used for Test matches, but the Hazelaarweg ground in Rotterdam is about seven metres below sea level, while the VRA ground in Amstelveen is about 3.3m below. Both have staged official one-day internationals."

Steven Lynch is the editor of the Wisden Guide to International Cricket 2013